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A theoretical model for the generation of thermo-acoustic waves from a heated point source in a free-space and a half-space is proposed, where the source is suspended over a substrate. By directly applying the analytical results of a point source to a thin line thermo-acoustic speaker, the acoustic pressure field generated by the periodically heated thin line can be derived using a mathematical integration technique. To further generalize the results from a thin line speaker to a thin line array, the acoustic pressure response generated by the line array speaker can also be implemented in both free- and half-spaces. In this work, the characteristics of pressure fields generated by the thin line array are investigated in detail. The established model is well validated by comparing with the existing experimental results. The present findings not only can be extended to investigate thermo-acoustic responses generated by arbitrary sources, and also it can provide important design guidelines for the manipulation and optimization of thin line array thermo-acoustic devices. [ABSTRACT FROM AUTHOR]

The possibility to improve thermoelectric performance of carbon-based quantum devices is of fundamental and importance in the fields of energy conservation, environmental protection, and green energy. Here we propose an effective avenue to enhance the thermoelectric figure of merits (TE-FOMs) of an all-carbon quantum device with the help of first-principles methods, and the device is constructed by a zigzag-edged trigonal graphene (ZTG) connected with zigzag-edged graphene nanoribbons (ZGNR) electrodes through the carbon atomic chains (CACs). Using a gate field, the spin-up transmission peak can be tuned from the position below the Fermi level to that above the Fermi level. However, the position of the spin-down transmission peak above the Fermi level is insensitive to the gate field. Therefore, the device can be converted from the p type to n type for the spin-up component by a gate field, while for the spin-down component the device remains n type. Meanwhile, we also find that the charge (spin) TE-FOMs at the Fermi level can be increased to about eight (three) times as compared with the case in the absence of the gate field. These TE-FOMs can also be significantly improved by tuning the incident electron energy and temperature. [ABSTRACT FROM AUTHOR]

We investigate the magnetic symmetry of the topological antiferromagnetic material Mn 3 Ge by torque measurements. Below the Néel temperature, detailed angle-dependent torque measurements were performed on Mn 3 Ge single crystals in directions parallel and perpendicular to the Kagome basal plane. The out-of plane torque data exhibit ± sin θ and sin 2 θ behaviors, of which the former results from the spontaneous ferromagnetism within the basal plane and the latter from the in- and out-of-plane susceptibility anisotropy. The reversible component of the in-plane torque exhibits sin 6 φ behavior, revealing the six-fold symmetry of the in-plane magnetic free energy. Moreover, we find that the free energy minima are pinned to the direction of spontaneous ferromagnetism, which corresponds to the maxima of the irreversible component of the in-plane torque. We provide an effective spin model to describe the in-plane magnetic anisotropy. Our results demonstrate that the ground state of Mn 3 Ge is described by the coexistence of a strong six-fold antichiral order and a weak ferromagnetic order induced by second-order spin anisotropy. [ABSTRACT FROM AUTHOR]

Oxygen vacancy associate defects were studied by electron paramagnetic resonance (EPR) for the perovskite oxide CaCu 3 Ti 4 O 12 (CCTO), which have a colossal dielectric constant. It is found that the EPR line width of the Cu 2+ –host signal of CCTO correlates with its permittivity. A new signal was found in the second differential of the Cu 2+ –host signal, which we think is associated with a specific copper–oxygen vacancy defect. This signal shows a negative g factor shift with temperature, suggesting a contribution to the conduction. Assuming solid state reactions between the various defects and using the mass action law, we offer a more specific relation between permittivity, the content of oxygen vacancy and the new signal, which might be useful for an indirect but fast oxygen vacancy content determination. [ABSTRACT FROM AUTHOR]

This paper describes the formation and properties of Cu and Cu(Ag) films on a Ru/Si substrate using electrochemical atomic layer deposition. The process was performed layer-by-layer using underpotential deposition (UPD) and surface-limited redox reactions. The first Cu atomic layer was deposited on the Ru/Si substrate via UPD. Using UPD, atomic layered of Pb, which acts as a sacrificial layer, was applied on the Cu layer. Then, a Cu 2 + solution was flushed into the cell at an open-circuit potential, and the Pb layer was exchanged for Cu via redox replacements. The above sequences were repeated 500 times to form a Cu film. The Cu(Ag) alloy films were formed using Cu–UPD and Ag–UPD in predetermined sequences. The lowest electrical resistivity achieved was 3.6 and 2.2 μΩ cm for the Cu film and Cu(Ag) film, respectively, after annealing at 400 °C. Due to the self-limiting reactions, the process has the ability to deposit atomic layers to meet the requirement of Cu interconnects. [ABSTRACT FROM AUTHOR]

The electrical properties of transparent Al-doped tin oxide (SnO 2 ), N-doped SnO 2 , and AlN-doped SnO 2 thin films were studied. The Al-doped tin oxide (SnO 2 ) thin films all show n-type conduction regardless the annealing condition. The n-type conduction of the as-deposited N-doped SnO 2 , and AlN-doped SnO 2 thin films could be converted to p-type conduction by annealing the films at an elevated temperature of 450 °C. XPS analysis verified that the substitution of N ions in the O ion sites in the annealed N-doped SnO 2 and AlN-doped SnO 2 thin films were responsible for the n–p conduction transition. The conduction of the annealed N-doped SnO 2 and AlN-doped SnO 2 thin films could be converted back to n-type conduction by thermally annealing the films at higher temperature, over 450 °C. The p–n conduction transition is related with the outgassing of N ions in the p-type N-doped SnO 2 and AlN-doped SnO 2 thin films. Remarkably, we found that the Al content can retard the outgassing of N ions in the p-type N-doped SnO 2 and AlN-doped SnO 2 thin films and prolong the p–n conduction transition temperature above 600 °C. XPS analysis revealed that the formation of the Sn N Al bond improved the stability of the N ions in the AlN-doped SnO 2 thin films. I – V curve of the p-type AlN-doped SnO 2 /n-type fluorine-doped SnO 2 junction exhibited clear p–n junction characteristics, a low leakage current under the revised bias (1.13 × 10 −5 A at −5 V), and a low turn-on voltage (3.24 V). p-Type AlN-doped SnO 2 /n-type fluorine-doped SnO 2 junction exhibited excellent transmittance (over 90%) in the visible region (470–750 nm). [ABSTRACT FROM AUTHOR]

We propose a time-dependent heat engine based on a single quantum dot (QD) sandwiched between two metallic electrodes. An external time-dependent field is applied on the single QD, which induces the periodic oscillation of energy levels inside the QD. Thus, the multiple transport channels are opened, resulting in the occurrence of the photon-assisted work regions for the heat engine. When an external magnetic field is presented, a photon-assisted single-spin heat engine is achieved. In some energy regions, the heat engine can be used to produce the single-spin current. Our results presented here indicate a way to fabricate the photon-assisted QD thermospin devices. [ABSTRACT FROM AUTHOR]

Abstract: The in vitro degradation behavior of poly-l-lactide (PLLA), PLLA/aragonite pearl powder and PLLA/vaterite pearl powder scaffolds was investigated. The scaffolds were soaked in phosphate buffer solution (PBS) up to 200days. Scanning electron microscopy (SEM), gel permeation chromatography (GPC), and differential scanning calorimetry (DSC) were used to observe any degradation of the scaffolds. Degradation behaviors such as changes in pH, porosity, bulk density, water absorption, weight loss and mechanical properties were discussed. The results show that a gradual increase of the pH in composite scaffolds can decrease the rate of hydrolysis of PLLA. PLLA/vaterite and PLLA/aragonite scaffolds have a similar degradation behavior but a slower rate of degradation than PLLA. [Copyright &y& Elsevier]

The enrichment and utilization of low-concentration coal bed methane (LCCMM) will provide a fuel source, will ensure safety from flammable gas release and will prevent significant greenhouse gas emissions. One of the special challenges in dealing with LCCMM originates from the presence of O2, which is difficult to process economically and explodes easily. In this work, we studied oxygen-bearing LCCMM with a CH4concentration of 20% and developed a safe and effective enrichment method for LCCMM: Proportion Pressure Swing Adsorption (PPSA), which used a mixture of active carbon (AC) and carbon molecular sieves (CMS) as adsorbents. With this method, CH4and O2in LCCMM can be adsorbed simultaneously because CH4is mostly adsorbed by active carbon and O2is mostly adsorbed by the CMS. Therefore, the concentration of CH4and O2is well controlled and does not exceed the explosive limit during the adsorption and desorption processes. The impact of bed length on LCCMM by PPSA was investigated. We have demonstrated the safety and feasibility of PPSA for obtaining 30% CH4from LCCMM, with 20% CH4in air as a feed stock. Our results showed that the O2concentration can be controlled well and does not exceed the explosive limit in both adsorption and desorption, and the CH4concentration in the desorption gas can be increased to more than 30% by adjusting the bed length and mass ratio of the AC and CMS. [ABSTRACT FROM PUBLISHER]

Abstract: X-ray absorption near edge structure (XANES) study of Co K-, Co L 2,3-, O K-, and Ca L 2,3-edges on a series of polycrystalline Ca2.9Ln0.1Co4O9+δ (Ln=Ca, Dy, Ho, Er and Lu) are presented. The high similarity of Co K-edge spectra of the doped and the undoped samples indicate that the average valence of Co is slightly higher than 3+ and it is not varied for different dopants. The variation of the intensity of the Co L 2,3-edge indicates that the number of Co 3d unoccupied states and thermoelectric power shows an opposite trend. According to the O K-edge spectra, the electrical resistivity and Co4+ 3d–O 2p hybridized unoccupied states also show an opposite trend, which is consistent with our results that a lesser amount of Co4+ leads to a larger thermoelectric power. There is a monotonic decrease of Ca L 2,3-edge intensity with decreasing ionic radius of the Ln element, which partially substituted for Ca. This could be attributed to a decrease of Ca 3d–O 2p hybridization with decreasing ionic radius of Ln. [Copyright &y& Elsevier]

Abstract: This paper investigates numerical method for predicting wind field and pollutant dispersion in an urban area with crowded buildings and heavy traffic. Large eddy simulation is employed in numerical computation with Lagrangian dynamic model to close the subgrid scale stress. The fine grids are required in numerical simulation of micro-atmospheric flows in an urban area with crowded and complex building-streets. To realize the numerical simulation on available computer resources a domain decomposition method and a combined model for the building-street layout are proposed that the computed domain of an urban area is decomposed into a central area, where the pollution is the major concern and a surrounding region where the pollutant distribution is not concerned. The combined flow model is proposed for the complex building-street layout that the fine grid mesh and exact flow boundary conditions are prescribed in the central area while the buildings are treated as roughness elements in the surrounding region where the coarse grids are used. The proposed numerical method is applied to simulate the wind field and pollutant dispersion from vehicle exhaust in the Rua Do Campo area of Macau (referred to the site hereafter). The wind speed and temperature fields are computed from 7 am on September 6 2005 to 7 am of the next day and the pollutant concentration field is computed from 7 am to 6 pm on September 6 2005. The results show fairly good agreement with the field observation. The wind field and pollutant concentration distribution are demonstrated in the site by proposed combined model and they are compared with those computed by drag element model in whole computational domain. The results show that the combined model is an appropriate method for predicting wind field and pollutant dispersion in the crowded building area. The paper also reveals the relevance of buoyancy effect in the prediction of urban atmospheric environment. [Copyright &y& Elsevier]

Abstract: We investigate theoretically the electronic transport through a parallel-coupled double quantum dot (DQD) molecule attached to metallic electrodes, in which the spin-flip scattering on each quantum dot is considered. Special attention is paid to the effects of the intradot spin-flip processes on the linear conductance by using the equation of motion approach for Green’s functions. When a weak spin-flip scattering on each quantum dot is present, the single Fano peak splits into two Fano peaks, and the Breit–Wigner resonance may be suppressed slightly. When the spin-flip scattering strength on each quantum dot becomes strong, the linear conductance spectrum consists of two Breit–Wigner peaks and two Fano peaks due to the quantum interference effects. The positions and shapes of these resonant peaks can be controlled by using the magnetic flux through the quantum device. [Copyright &y& Elsevier]

Rapid urbanization and industrialization in southern Jiangsu Province have consumed a huge amount of arable land. Through comparative analysis of land cover maps derived from TM images in 1990, 2000 and 2006, we identified the trend of arable land loss. It is found that most arable land is lost to urbanization and rural settlements development. Urban settlements, rural settlements, and industrial park-mine-transport land increased, respectively, by 87 997 ha (174.65%), 81 041 ha (104.52%), and 12 692 ha (397.99%) from 1990 to 2006. Most of the source (e.g., change from) land covers are rice paddy fields and dryland. These two covers contributed to newly urbanized areas by 37.12% and 73.52% during 1990–2000, and 46.39% and 38.86% during 2000–2006. However, the loss of arable land is weakly correlated with ecological service value, per capita net income of farmers, but positively with grain yield for some counties. Most areas in the study site have a low arable land depletion rate and a high potential for sustainable development. More attention should be directed at those counties that have a high depletion rate but a low potential for sustainable development. Rural settlements should be controlled and rationalized through legislative measures to achieve harmonious development between urban and rural areas, and sustainable development for rural areas with a minimal impact on the ecoenvironment. [Copyright &y& Elsevier]

Abstract: Based on the slave boson approach and the Keldysh Green’s function technique, we investigate theoretically the transport properties of a mesoscopic structure consisting of a Kondo quantum dot with a side-coupled noninteracting quantum-dot array at zero temperature, in which only the Kondo dot is coupled to the leads. When the interdot coupling strengths inside the sided-coupled noninteracting quantum-dot array are compared with the Kondo temperature of the single Kondo dot, the local density of states (LDOS) may be decomposed into one Breit–Wigner and multiple Fano line shapes due to the Fano–Kondo interactions when the appropriate system parameters are considered. The odd–even parity of the linear conductance is also found with the number of side-coupled quantum dots in the array changing, in which the energy levels of quantum dots are pinned at the Fermi energy in the leads. The odd–even parity is broken when the energy levels of side-coupled quantum dots in the quantum array depart from the Fermi energy. [Copyright &y& Elsevier]

Abstract: In this Letter, we studied the electronic transport through a parallel-coupled double quantum dot (DQD) molecule including impurity effects at zero temperature. The linear conductance can be calculated by using the Green''s function method. An obvious Fano resonance arising from the impurity state in the quantum dot is observed for the symmetric dot-lead coupling structure in the absence of the magnetic flux through the quantum device. When the magnetic flux is presented, two groups of conductance peaks appear in the linear conductance spectra. Each group is decomposed into one Breit–Wigner and one Fano resonances. Tuning the system parameters, we can control effectively the shapes of these conductance peaks. The Aharonov–Bohm (AB) oscillation for the magnetic flux is also studied. The oscillation period of the linear conductance with π, 2π or 4π may be observed by tuning the interdot tunneling coupling or the dot-impurity coupling strengths. [Copyright &y& Elsevier]

Aims: To identify beneficial oxygen vectors for Phaffia rhodozyma in liquid cultures, and to evaluate their use to improve the oxygen transfer and carotenoid production in the yeast cultures. Methods and Results: Several liquid hydrocarbons were tested as oxygen vectors for improving the yeast growth and carotenoid production in shake-flask cultures of P. rhodozyma. While all nontoxic organic liquids (Log P: ≥5·6) showed a positive effect, n-hexadecane was proved to be the most beneficial for the yeast growth and carotenoid production. The addition of 9% (v/v) n-hexadecane to the liquid medium at the time of inoculation was found to be optimal, increasing the carotenoid yield by 58% (14·5 mg l−1 vs 9·2 g l−1 in the control) and the oxygen transfer rate (OTR) by 90%. Conclusions: The addition of n-hexadecane to shake-flask cultures of P. rhodozyma significantly improved the oxygen transfer in culture, thus increasing the carotenoid production. Significance and Impact of the Study: Use of organic oxygen vectors such as n-hexadecane may be a simple and useful means for enhancing oxygen transfer and carotenoid production in liquid fermentation of P. rhodozyma. [ABSTRACT FROM AUTHOR]

Abstract: In order to accurately predict plastic anisotropy in interstitial free (IF) steels with high r-values, the full constraint (FC) model and the Pancake version of the relaxed constraint (RC) model were used to simulate the r-values in several IF steel sheet samples on the basis of Taylor theory, wherein either two families of slip systems (namely {110}+{112}〈111〉) or three families of slip systems (namely {110}+{112}+{123}〈111〉) were considered. It was found that the r-values calculated by the Pancake version of the RC model using two families of slip systems are in more satisfactory agreement with mechanically experimental results than the other models. This model seems to describe the nature of plastic behavior for the experimental IF steels well. [Copyright &y& Elsevier]

We theoretically study the quantum entanglement of two interacting electrons in an asymmetric double coupled quantum dot under an ac electric field. The electron–electron correlation plays an important role in forming entangled states of the system. We show that the maximally entangled Bell states can be prepared when a resonant transfer occurs between two localized states under the sufficiently strong Coulomb interaction in such an asymmetric system, where entanglement can be manipulated by using an ac field. Our analytical results are in good agreement with the numerical results from the Floquet theory. [Copyright &y& Elsevier]

We theoretically analyze the dynamical behaviors of an interacting electron–hole pair in a double coupled quantum dot molecule in radiation pulses. It is found the maximally entangled Bell states can be prepared when a resonant transfer occurs between two localized states. The strength and duration of selective light pulses for producing maximally entangled states are identified by analytic and exact numerical solution of the quantum dynamical equations under the stronger Coulomb interaction. [Copyright &y& Elsevier]

We investigate the dynamical behaviors of an interacting electron–hole pair in a double coupled quantum dot molecule under an ac electric field. We theoretically analyze the phenomenon of localization of an exciton in the quantum system, and indicate the conditions that dynamical localization occurs. The attractive Coulomb interaction plays an important role in forming localization and entangled states of the system. It is found that they move between the two coupled dots as a whole even if the strength of the electric field is much stronger than the Coulomb interaction. The dynamics of the exciton are mainly confined in a low-energy subspace, which is constructed by two localized states. Quantum entanglement of the exciton in this system can be manipulated by using the ac field. The same results are obtained numerically within Floquet theory. [Copyright &y& Elsevier]

The heat-treatment parameters of both the calcination and the reaction heat treatment play a crucial role in the achievement of high quality (Bi,Pb)-2223/Ag tapes. The melting process has been successfully used for the processing (Bi,Pb)-2212 in order to achieve good grain alignment and connection. In this paper, we report the partial-melting process to fabrication of (Bi,Pb)-2223/Ag tapes and discuss the results of the effects of the partial-melting treatment on microstructure and phase development. The results indicated that the tapes prepared by partial-melting process exhibit higher grain packing density and better texture than those prepared by the normal process. As a result, the critical current density is improved. [Copyright &y& Elsevier]

The cold rolling texture in a molybdenum sheet was simulated using different plasticity models. The Lamel model made a prediction closer to the experimentally determined texture than the “full constraints” (FC) Taylor model and the “relaxed constraints” (RC) Pancake model. However, the Lamel model did not perform as well as in previously investigated low-carbon steels. Having observed that the experimental fibre-profiles appear intermediary between the predictions of the Lamel and the Pancake model, two revised compromise models are developed, by which the simulated results can be further improved. The applicability of the various models is physically motivated. [ABSTRACT FROM AUTHOR]

Focuses on an experiment which investigated electroluminescence from high density polyethylene films and also examines the temporal behavior of carriers injected into the polymer. Detailed information on the experiment; Indepth look at the results; Discussion on the findings; Conclusions on the experiment.

Focuses on a study which examined the electric field range of electroluminescence (EL) in insulated polymers. How data was collected and analyzed; Characteristics of EL; What the study revealed; Discussion of the results.

Abstract: The electronic structure of Mg doped Fe3O4 thin films were studied by X-ray absorption near edge structure (XANES). Measurements were performed near Mg, O and Fe K-edges. Mg K-edge spectra show a gradual evolution from a much broader three-feature structure into characteristic MgO spectrum as x varies from 0.1 to 1. The O K-edge XANES spectra indicate that the Fe 3d–O 2p hybridized states decrease as Mg concentration increases. Results of Fe K-edge XANES reveal the Mg was doped preferably into B-site more. All spectra indicate the change of crystal and electronic structure from spinel to rocksalt, start at x >0.5. [Copyright &y& Elsevier]

To review and compare policies released by the FDA and EMA regarding PRO studies in drug development. While health-related quality of life (HRQL) is viewed as a type of PRO by the EMA, the FDA does not include HRQL in the definition of PRO. Conclusions FDA and EMA policies have different criteria on PRO studies in terms of HRQL as endpoints, PRO instruments and study designs. [Extracted from the article]

A collinear resonance ionisation spectroscopy setup has been developed with the aim to study the nuclear properties of more exotic isotopes. It is developed on the basis of a recently-commissioned collinear laser spectroscopy, and could in principle measure the hyperfine structure spectra of studied isotopes using both laser-induced fluorescence and laser resonance ionisation approaches. In this paper, the latest technique development, the progress on the test of the vacuum system and the ion beam transportation, and the near-term offline experimental plans are presented. [ABSTRACT FROM AUTHOR]

Abstract: This paper studies a sequence-dependent scheduling problem incorporating order delivery, motivated by satellite imaging scheduling. A set of jobs is to be processed on a single machine and each job belongs to a specific group. The completion time of a group is the moment when all jobs belonging to this group are completed. The problem is to determine a processing sequence of the jobs such that the sum of weighted completion times over all groups is minimized. We present a binary integer program to formulate the studied problem and then develop an O(n 22 n ) dynamic programming algorithm for determining optimal solutions. To produce approximate solutions within an acceptable time, we design a tabu search algorithm, an iterated local search algorithm and a genetic algorithm. Computational experiments are conducted to study the performance of the integer program and the solution algorithms. Numerical statistics suggest that the binary integer program can reach optimal solutions faster than the integer program existing in the literature, and the iterated local search algorithm outperforms other approaches when the number of jobs increases. [Copyright &y& Elsevier]

Abstract: Epitaxial Cu3Sn and Cu6Sn5 grown by liquid-phase electroepitaxy (LPEE) have been demonstrated in this work. X-ray diffraction analysis reveals that LPEE-grown Cu3Sn and Cu6Sn5 grew in particular directions (planes) with respect to the electron flow. LPEE-grown Cu3Sn grew in the 〈020〉 and 〈400〉 directions, and LPEE-grown Cu6Sn5 grew in the 〈204〉 and directions. With the aid of a molecular simulation software tool, we conclude that the particular growth directions represent the low-resistance paths for electron flow. This means that, along those particular directions in the LPEE-grown Cu–Sn compounds, the traveling electrons would be scattered least by the lattice. Thus, as the electromigrating Cu atoms form Cu–Sn compound, the newly forming Cu–Sn unit cells would orientate themselves in those particular growth directions to facilitate electron flow. Then, the well-oriented newly formed Cu–Sn compound unit cells can incorporate the growth of the highly orientated LPEE-grown Cu–Sn compounds. In addition, the anisotropy of a number of properties of LPEE-grown Cu3Sn and Cu6Sn5, i.e. coefficient of thermal expansion, Vickers microhardness and electrical properties (resistivity, carrier mobility and carrier concentration), along the particular orientations were measured and reported. [Copyright &y& Elsevier]

• The wear performance of the defected rail materials under various slip ratios and contact stresses was investigated. • The surface damage of the defected rail materials under various slip ratios and contact stresses was studied. • The effect of slip ratio and contact stress on crack propagation mechanisms near the dent was discussed. The defects on rail surface may have negative effects on the rolling contact fatigue (RCF) performance of the rail materials. This investigation researched on the RCF behaviors of the defected rail materials under various slip ratios and contact stresses. The results show that both the wear loss and the average crack length increase if the slip ratio or the contact stress increases. Moreover, the surface damage characteristics change from simple adhesion spots to significant fatigue crack grouping when slip ratio and contact stress rise. Finally, the experimental results also highlight that the slip ratio provides the deformation area for crack initiation whereas the contact stress accelerates the crack propagation by emphasizing the geometric effects. [ABSTRACT FROM AUTHOR]

Abstract: Interlaminar shear strength (ILSS) of a two-dimensional carbon fiber reinforced silicon carbide composite (2D-C/SiC) was investigated by compression test at elevated temperature in both air and vacuum. The fractured surfaces were observed by a scanning electron microscope. The results show that ILSS in air decreased when the material was tested at the temperatures lower than the preparation temperature (∼900°C), among which the strength determined at 700°C was the smallest. In contrary, ILSS in vacuum increased with increasing temperatures until 900°C, and then decreased at 1200°C. The different variation of ILSS with temperature is closely related to the damage mechanisms under the shear load. The main forms of the damages in vacuum, involve debonding of the interface between the fibers (or fiber bundles) and the matrix, matrix cracking and fiber pullout. However, the interaction between the oxidation of the constituents and above damages dominated damages accumulation and led to the contrary dependency of ILSS on the temperature in air. [Copyright &y& Elsevier]

Abstract: The growth of grain size of CuInGaSe2 and the Ga distribution in the thin film CuInGaSe2 solar cell devices fabricated using a sputtering CuInGa ternary target have been studied. It was observed, adding a thin CuGa layer on top of the surface of CuInGa ternary precursor would increase the Ga concentration, and thus the energy gap in the space-charge region after selenization. As a result, the open circuit voltage (V oc) of the device was increased by 15%. The SEM and XRD studies further show that the addition of a CuGa layer enhanced the growth of grain size of CuInGaSe2 during selenization and increased the conversion efficiency of the solar cell devices by 27% (from 6.3% to 8%). [Copyright &y& Elsevier]

Abstract: In this paper, residual stress measurements were made on aluminium alloy 2A12T4 open holes after cold expansion. By contrast, a finite element method (FEM) was also used to analyze the residual stress distribution around cold expansion hole. Then a series of uniaxial fatigue tests were carried out using specimens containing non-cold expanded holes and cold expanded holes to assess the effect of direct cold expansion process on fatigue performance of open hole. At last the fracture morphology of the specimens after fatigue test was examined by scanning electron microscopy. The results reveal that direct cold expansion technique could elevate about six times fatigue life. After cold expansion, fatigue crack of open holes always initiates on entrance face. [Copyright &y& Elsevier]

Abstract: In this paper, the effect of surface finish of open holes on the fatigue life has been studied. Four defects of the surface finish are simulated. They are scratch, void, inclusion and roundness. Firstly, the effect of the four defects on the stress distributions around the holes has been studied by the finite element method (FEM). The fatigue lives are determined based on the stress distributions by the method of nominal stress approach. The results show that the fatigue lives are dependent on the quantity of the surface finished. There are the critical defect values of scratch, void and inclusion, smaller than which there is no effect of the surface finish on the fatigue life. For these three defects, the fatigue lives decrease with the increasing of the values of the defects. It is the same to the defect of roundness, e.g. the bigger roundness tolerance is, the shorter the life is. Further, an approximate quadratic curve has been found for the relationship between the roundness tolerances and their logarithmic fatigue lives. [Copyright &y& Elsevier]

Abstract: Similarity assessment and retrieval of solid models play a key role in achieving reuse of huge amounts of solid models. In this paper, an approach to multiresolutional similarity assessment and retrieval of solid models is presented. First the dilation based multiresolutional skeleton of a solid model is defined, which is adopted as the shape descriptor of solid models in the approach; Then the detailed algorithm of generating the proper DBMS of a solid model through multiresolutional dilation is described; After that the methods of multiresolutional matching based on the DBMS graph and the multiresolutional similarity assessment and retrieval of solid models based on multiresolutional matching are presented; Finally some preliminary test results are given. [Copyright &y& Elsevier]

Abstract: Numerical calculations with Kachanov–Rabotnov damage law have been performed to study the creep damage development of circumferential notched specimens under cyclic loading. The emphasis was placed on the roles of specimen geometry and loading. The results show that the distributions of creep stress and damage are different under cyclic loading from that under a constant amplitude load. Different specimen has different damage distribution. The development of creep damage in the minimum cross-section varies reasonably with the notch radius. The evolution of creep damage is clearly affected by the mean load, loading cycle (frequency) and ratio. With the other two factors unchanged, each of the following three factors, larger mean load, higher loading frequency and smaller loading ratio, can cause the damage to develop faster. [Copyright &y& Elsevier]

Single molecule-based devices have been one of the most candidates to realize the miniaturization of traditional electronic devices. Here we investigate the spin-polarized transport properties of an iron-complex molecule sandwiched between two ferromagnetic zigzag-edged graphene nanoribbon electrodes based on the non-equilibrium Green's function formalism combined with the density functional theory. When the iron-complex molecule rotates, a single-spin switching effect is observed at the Fermi level, and meanwhile a perfect spin filtering effect appears in the molecular device. As the electric bias increases, an obvious negative differential electrical resistance is observed. In addition, we also find a negative differential thermoelectric resistance in the absence of the electric bias under a small molecular rotation, and the sign and magnitude of the thermally driven current can be tuned by the temperature. These theoretical findings imply that the iron-complex molecular devices have potential applications in the next-generation spin electric and thermoelectric devices. [Display omitted] [ABSTRACT FROM AUTHOR]

To compare the patient-reported outcomes (PRO) labeling for oncology products approved by the Food and Drug Administration (FDA) and European Medicines Agency (EMA) between 2017 and 2018. Methods FDA Drug Approval Packages (DAP) and EMA European Public Assessment Reports (EPAR) were reviewed for drugs with oncology indications approved by both FDA and EMA between 2017 and 2018. [Extracted from the article]

The temperature and dc bias stability of the dielectric constant and loss tangent of CaCu 3 Ti 4 O 12 samples sintered under different oxygen atmospheres are discussed. The results suggest that the metal-oxygen vacancy related defects not only provide the charge carriers for the conduction (defect doping) but also contribute to the huge permittivity in the way of defect dipoles repositioning under charge carrier hopping. The charge localization in a specific copper-oxygen vacancy defect complex is the reason of the huge and stable permittivity and low dielectric loss in the middle temperature range, 90 K-200 K (20 Hz), while the implementation of the large barrier layer height needs a contribution by the titanium oxygen vacancy related trap charges in the grain boundaries, which also lead to a second permittivity stable range in a higher temperature range 200 K–300 K. [ABSTRACT FROM AUTHOR]

The correlation between conductance, capacitance and oxygen content is discussed in the colossal dielectric permittivity perovskite oxide CaCu 3 Ti 4 O 12 . We found an unusual positive conductivity-permittivity relation which is very sensitive to the oxygen content. In particular, we ascribe the oxygen content sensitivity of both the capacitance and the conductance to a repositioning of charges on oxygen vacancy related defects and/or on the migration of the defects themselves. We find that in the charge repositioning process a Jonscher type of global conduction is accompanied by a Debye-type local electronic relaxation in and between the boundaries of a specific grain. A closer investigation of these processes suggest that the local polaronic relaxation of charges on oxygen vacancy related defects is mainly responsible for the large dielectric constant of CaCu 3 Ti 4 O 12 and also for the ac conduction at low to medium temperatures. [ABSTRACT FROM AUTHOR]

Using the density functional theory combined with the Keldysh non-equilibrium Green's function methods, we investigate the thermally (or voltage)-induced spin transport properties of a two-probe device consisting of a carbon atom chain sandwiched between two zigzag graphene nanoribbon (ZGNR) electrodes. When the edge of one ZGNR electrode is partially doped by B atoms, the flowing direction of thermal single-spin current can be reversed in contrast with the undoped case. In addition, when a voltage is applied across the carbon-based device at room temperature, a giant rectification ratio of 10 4 is observed which mainly originates from the band-structure incompatibility between two ZGNR electrodes in the voltage window. Moveover, in the high-voltage region, a single-spin negative differential resistance is also observed in the carbon-based device. Our findings here suggest that the carbon-based systems can be used to design spintronic devices with multiple functions. [ABSTRACT FROM AUTHOR]

Based on first-principles calculations, we have systematically investigated the structural stability, electronic and magnetic properties of zigzag C 2 N nanoribbons (ZC 2 NNRs). Different from zigzag graphene nanoribbons (ZGNRs), the ground states of ZC 2 NNRs present ferromagnetic metal, antiferromagnetic semiconductor and spin semiconductor dependently on the edge configuration and width of nanoribbons. Our results suggest the ZC 2 NNRs have great potential applications in spintronic, thermoelectric and optoelectronic devices. [ABSTRACT FROM AUTHOR]

An organic/inorganic white-light emitting F8T2 (9,9-dioctylfluorene-co-bithiophene)/GaN heterojunction is reported. The white-light emission is produced by hybridizing the blue light (464 nm) emitted from the GaN MQWs and the yellow/green light (500–650 nm) emitted at the F8T2/p-GaN interface by electroluminescence (EL). The yellow/green light emission in the F8T2 layer is resulted from the carrier accumulation and Frenkel excitons at the F8T2/p-GaN junction interface. It is concluded that the energy barrier and large mobility discrepancy at the F8T2/p-GaN junction interface cause carriers accumulating in the F8T2 side near the F8T2/p-GaN interface. The accumulated carriers at the F8T2/p-GaN interface form Frenkel excitons by Coulombic interaction. Then, the Frenkel excitons recombine to radiate the yellow/green emission in the F8T2 layer. The International Commission on Illumination (CIE) coordinate of the white-light emitted from the present device is at (0.28, 0.30), which is very close to the standard white light (0.33, 0.33). [ABSTRACT FROM AUTHOR]

The spin thermoelectric performance of a polyacetylene chain bridging two zigzag graphene nanoribbons (ZGNRs) is investigated based on first principles method. Two different edge spin arrangements in ZGNRs are considered. For ferromagnetic (FM) ordering, transmission eigenstates with different spin indices distributed below and above Fermi level are observed, leading directly to a strong spin thermoelectric effect in a wide temperature range. With the edge spins arranged in the antiferromagnetic (AFM) ordering, an obvious transport gap appears in the system, which greatly enhances the thermoelectric effects. The presence of a small spin splitting also induces a spin thermoelectric effect greater than the charge thermoelectric effect in certain temperature range. In general, the single-molecule junction exhibits the potential to be used for the design of perfect thermospin devices. [ABSTRACT FROM AUTHOR]

Using first-principles methods, we have investigated magnetic properties and thermospin effects of zigzag silicene nanoribbons (ZSiNRs) absorbed by a single Si atom. After a relaxation, a steady dumbbell-like structure is formed, which induces a weaker antiferromagnetic (AFM) coupling between two zigzag edges. Therefore, a band gap is opened, meanwhile the adsorbed ZSiNRs show a spin semiconducting property. A large spin thermopower and weak charge thermopower in adsorbed ZSiNR-based devices can be simultaneously achieved, which is attributed to a nearly perfect mirror symmetry of spin-up and spin-down transmission spectra relative to the Fermi level. [ABSTRACT FROM AUTHOR]